Mold (mildew), mushrooms, and yeast are all types of fungi. Fungi are found both indoors and outdoors. Hundreds of different kinds of mold are commonly found in the United States and New York City.
The best way to prevent mold growth in your apartment is to remove water and moisture sources. Fixing leaks, drying damp areas, and removing humidity from the air (e.g., using a dehumidifier in basements; cracking a window while taking a shower in bathrooms with no exhaust ventilation) will help stop mold growth and keep it from coming back.
To address small areas of mold: